Mechanism of prostaglandin E2-induced increase of proximal sodium reabsorption in the rat.
Prostaglandin E2, when infused directly into the renal interstitium, enhances sodium reabsorption by the superficial proximal convoluted tubules of anesthetized Sprague-Dawley rats. The present study was designed to investigate the role of angiotensin II in the prostaglandin E2-induced stimulation of proximal sodium reabsorption. Micropuncture at the superficial late proximal tubule demonstrated a significant increase in the fractional reabsorption of sodium from 39.9 +/- 2.3% in control conditions to 51.8 +/- 3.0% (n = 9, P less than 0.01) during the renal interstitial infusion of prostaglandin E2. The stimulatory effect of prostaglandin E2 on proximal sodium reabsorption was markedly attenuated by pretreatment with saralasin. During intravenous saralasin infusion, prostaglandin E2 did not significantly change the fractional reabsorption of sodium from 42.2 +/- 5.8 to 45.4 +/- 6.0% (n = 7, NS). In summary, the stimulatory effect of renal interstitial infusion of prostaglandin E2 on proximal sodium reabsorption was attenuated by pretreatment with saralasin. Therefore renal interstitial infusion of prostaglandin E2 may enhance proximal sodium reabsorption, at least in part, through stimulation of angiotensin II production in the rat kidney.
Kinoshita
Y
Y
Department of Physiology, Mayo Clinic, Rochester, Minnesota 55905.
Knox
F G
FG
D000042:Absorption; D000818:Animals; D001696:Biomechanical Phenomena; D015232:Dinoprostone / Q000494:pharmacology*; D007687:Kidney Tubules, Proximal / Q000378:metabolism*; D008297:Male; D011677:Punctures; D051381:Rats; D011919:Rats, Inbred Strains; D012504:Saralasin / Q000494:pharmacology; D012964:Sodium / Q000378:metabolism*
D012964:Sodium; D012504:Saralasin; D015232:Dinoprostone